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Wymelenberg S; Institute of Medicine (US). Science and Babies: Private Decisions, Public Dilemmas. Washington (DC): National Academies Press (US); 1990.

Cover of Science and Babies

Science and Babies: Private Decisions, Public Dilemmas.

Wymelenberg S; Institute of Medicine (US). Washington (DC): National Academies Press (US); 1990.

5 Prenatal Care: Having Healthy Babies

One of the best measures of a nation's health is its infant mortality rate—the number of babies born alive who die before their first birthday. Because the future of a country depends on the well-being of its children, the health of those children is a major concern.

In highly developed countries the majority of children are healthy. Like much of the industrialized world, during this century the United States made a great deal of progress in reducing the number of deaths among newborns and infants. During the 1980s, however, that progress stagnated; in some U.S. cities infant mortality actually increased.

Although the United States was never a world leader in reducing the mortality rate of its newborns, in 1918 it ranked sixth among 20 selected countries. It wasn't until the 1980s that the United States actually began to lose ground. In 1987, the most recent year for which there are data, the United States ranked nineteenth among industrialized countries in infant mortality, behind such nations as Spain, Singapore, and Hong Kong, where infant mortality rates were 9 per 1,000 births. The lowest newborn death rates are 6 per 1,000 births, found in Japan, Finland, and Sweden.

In 1987 more than 10 out of every 1,000 newborns in this nation died. The death rate for white infants was 8.6 per 1,000 births. The mortality rate for black babies in 1987, however, was close to a staggering 18 per 1,000 newborns, more than twice as high as the rate for white babies. The mortality rate for black newborns in the United States matches the entire national infant mortality rates in Poland, Hungary, Portugal, and Costa Rica, which have the highest infant death rates among 32 nations studied by UNICEF.

The high death rate among newborns in this country is related strongly to the number of infants whose weight at birth is lower than normal for their gestational age or who were born prematurely. Low birthweight is defined as under 2,500 grams (5 lbs. 8 oz.); very low birthweight is under 1,500 grams (3 lbs. 5 oz.). Low birthweight is the result of inadequate fetal growth, and the lower the birthweight, the greater the immaturity and risk of death. A number of factors contribute to low birthweight: low socioeconomic status, a low level of education, childbearing very late or very early in the reproductive years, poor nutrition, medical problems, and substance abuse.

By providing necessary medical care and helping pregnant women improve their general health, prenatal care programs play an important role in alleviating risk factors and improving pregnancy outcomes, particularly if the care is adequate and obtained early. In its 1988 study of the health of infants and children, the Office of Technology Assessment (OTA) found that early and comprehensive prenatal care can improve the chances of overcoming low birthweight and infant mortality. Women who do not receive adequate maternity care, on the other hand, double the risk of having a low birthweight baby.

Because low birthweight has such a dominant effect on newborn mortality and on health problems in infants and children, it has become the focus of many professional and public groups. When the National Commission to Prevent Infant Mortality was formed in 1987 to develop a national strategy for reducing infant mortality, its first major report succinctly summarized the current state of infant health in this country:

What we found is that too many infants are born too small, too many are born too soon, and too many mothers never get decent care and guidance during their pregnancy.

No single reason can explain why the U.S. infant mortality rate stopped declining in the 1980s. Infant mortality is rooted in a broad, saddening array of factors such as poverty, absent fathers, physical and emotional abuse, poor housing, lack of parenting role models, and, increasingly, drug abuse.

One factor worth noting is the growing number of births of extremely tiny infants of approximately 500 grams (about 1 lb.) who are resuscitated but subsequently die. Some observers believe that the changes in managing and reporting the births of these extremely immature infants are partly responsible for leveling the infant mortality rate.

Furthermore, many professionals are concerned that the deepening poverty in this country and the steady decline in public funding for health services are having a negative impact on maternal health and infant mortality. While 48 states offer some prenatal care programs for poor women, restrictive eligibility requirements and a scarcity of clinics mean that such programs reach only a small percentage of the women who need them. In addition, during the recession of the early 1980s, many breadwinners lost their jobs and with them the employer-paid health insurance that often covered prenatal care. The Congressional Research Service reports that virtually all the increase in the number of uninsured Americans since 1980 is the result of declining employer-based coverage of dependents.

Many factors lead to the increase in infant mortality seen in this country, but this chapter concentrates on the important interactions between prenatal care, birthweight, and infant survival. It reviews the current status of health care services for women and babies in the United States, particularly the services available for pregnant women, since such care influences the health of the next generation. The chapter also surveys the many barriers that make prenatal care difficult to obtain for the very women who need it most.

Maternal and Infant Health—The Picture Today

Key measures of the health of an industrialized society are its rate of infant mortality, its percentage of low birthweight newborns, and what proportion of its pregnant women receive prenatal care. From the mid-1960s to the 1980s, the United States made considerable improvement in these areas. During the 1980s, however, progress toward reducing infant mortality stalled.

Among blacks, in 1985 and 1986 the national decline in infant deaths became so small it was statistically insignificant. For every state that recorded improvement in its mortality rate for black infants, there was a state in which the rate climbed. On a state-by-state basis, black infant mortality rates ranged from 12.7 to 24 per 1,000 births. The average was 18 deaths per 1,000 births, which is significantly higher than the national average of 10.4 percent for all races. The death rate for white infants ranged from 7.7 to 11.3 per 1,000 births.

Year-to-year fluctuations in the mortality rates for both black babies and white babies are to be expected, but observers at the OTA believe that the slowing of the decline in the infant mortality rate in this decade cannot be dismissed as a random variation in the trend.

The U.S. newborn death rate is related in large part to the high percentage of low birthweight infants. The United States ranks twelfth in the number of infants born with low and very low birthweights. Low birthweight is an important determinant of infant health and mortality. Most low birthweight babies are immature, which means they are born before they reach their normal growth and development in the uterus. As a result, they are more likely to die during infancy or to become children who require more medical care and hospitalization than the average child. Analysts at the Children's Defense Fund find that immaturity contributes to two-thirds of the deaths of babies in their first month of life. The OTA reports that in 1980 low birthweight infants represented less than 7 percent of all newborns in the United States but accounted for 60 percent of all babies who died in infancy.

Low Birthweight and Infant Mortality

Birthweight came to be viewed as an measure of fetal growth early in this century; a low birthweight was seen as an indicator of inadequate intrauterine growth or prematurity and the baby was not expected to live. Forty years ago the World Health Organization (WHO) adopted 2,500 grams (5 lbs. 8 oz.) as the weight below which newborns were considered to be of low birthweight. Although a low birthweight was often associated with an abbreviated gestation, in 1960 the WHO noted that this was not always true. An infant weighing less than 2,500 grams was not always premature but, instead, could be small for its gestational age.

Before 1950 most infant deaths occurred after the first month of life, generally as a result of environmental factors such as infections and poor nutrition. As the incidence of such deaths fell by mid-century, there was a shift in the timing of infant deaths. After the 1950s the majority of infant deaths occurred during the neonatal period, the four weeks immediately after birth. The causes of those deaths were rooted in the pregnancy and birth process and included birth injuries, asphyxia, congenital defects, and low birthweight.

The latter is a significant factor. In 1950 only 7.5 percent of newborns weighed 2,500 grams or less, yet two-thirds of the infant deaths that year occurred in among such low birthweight babies. Beginning in the 1960s the relationship between birthweight and infant mortality has been documented frequently in several countries and hospitals. The studies reveal that, compared with infants weighing a more normal 3,000 to 3,500 grams (6 lbs. 5 oz.) and up, babies weighing less than 2,500 grams are almost 40 times more likely to die in the weeks after their birth. The likelihood of death increases as birthweight decreases. If small babies survive the neonatal period, they continue to have a higher risk of death during their first year, accounting for 20 percent of infant deaths during that period.

Major advances in improving infant mortality have been achieved through saving the lives of premature infants, not in reducing the prevalence of low birthweight. In the late 1960s sophisticated monitoring and treatment methods were developed for premature infants whose undeveloped lungs did not function properly. In the 1970s neonatal intensive care units (NICUs) became part of most large hospitals. In the 1980s improvements in respiratory therapy and mechanical ventilation began to make it possible to save the lives of newborns with very low birthweights of less than 1,500 grams (3 lbs. 5 oz.).

The widespread use of NICUs is associated with a small percentage of children growing up with neurodevelopmental handicaps. Some have physical impairments that are the result of the technology itself. How serious these problems are as the child grows older and begins school and how they are affected by socioeconomic and other factors is not yet fully understood.

Babies born in hospitals with NICUs have a better survival rate than those born in hospitals without them. By reducing the death rate of very small newborns, NICUs have been the principal means for the decline in U.S. infant mortality rates in recent years. In reviewing the 1986 data, observers at the Children's Defense Fund conclude:

Any decline in the national neonatal mortality rate in 1986 presumably was not achieved because more infants were born healthy. Rather, more fragile infants survived the newborn period with the aid of expensive hospital technology.

In contrast, the enhancement of infant birthweight, which would improve the outcome for so many newborns, has been so slight that it has had little impact on mortality figures.

Some observers suggest that neonatal mortality rates ceased to drop because the reporting of births of extremely small newborns, those weighing less than 500 grams (about 1 lb.), has increased at many hospitals.

From 1981 to 1984 the number of reported births of these tiny infants rose more than those in any other category of birthweight in the United States. Almost all of these infants died during the newborn period. In earlier years such babies usually did not survive the birth process and were listed not as births but simply as fetal deaths. Today in many places they are counted as live births and, subsequently, as infant deaths. Some analysts believe one factor in the current slowdown of the infant mortality decline may be this difference in managing and reporting extremely immature births, rather than a real deterioration in the health of pregnant women.

Poverty and Infant Mortality

Others concerned with the rate of infant mortality in this country believe that an important factor in infant mortality rates is the progressive ''dis-insurance" of the working poor, the increase in the proportion of women and infants living in poverty, and the shrinking in real dollars of subsidized health services for pregnant women and children.

Poverty increases the chances of producing a low birthweight baby. The incidence of premature birth and inadequate fetal growth is greater among poor women. The causes are not clear; however, Paul H. Wise, of Harvard, and Alan Meyers, of Boston University, note there is evidence that prematurity and inadequate growth are related to elevated risk and reduced access to medical care:

Poor nutrition, small stature, increased stress, and obstetric complications can all affect birth weight and are more common among poor women. A risk often overlooked is the state of a woman's health prior to conception. In this context, the effect of poverty on birth outcome may represent in part a legacy of inferior health status of poor women both before and during their childbearing years.

Decreased spending on publicly funded health care in this country during the 1980s has paralleled the increase of poverty among women and children. In its 1988 book, Healthy Children: Investing in the Future, the OTA reports that from 1978 to 1984 the percentage of infants residing in poor families rose from 18 to 24 percent. At the same time, Medicaid expenditures in constant dollars per child recipient declined by 13 percent and federal funding for three important sources of primary health care for poor women and children—maternal and child health services, community health centers, and migrant health centers—declined in constant dollars by 32 percent.

Sara Rosenbaum of the Children's Defense Fund and her co-investigators found in 1986 that in 15 states hospitals denied admission to women about to deliver babies. In another 13 states hospitals were refusing to admit women who were not in "active" labor. "Patient dumping" was recorded in 6 other states. The researchers also found that one or more hospitals in 23 states required a cash deposit if a woman wanted to preregister for delivery. A woman who could not pay a deposit would not be admitted for delivery unless she was in advanced labor and was considered an emergency case.

The OTA found that putting health care out of the reach of increasing numbers of poor women and children would have had only a "modest effect" on the overall infant mortality rate by the mid-1980s. However, the report also pointed out:

Yet, for a particular infant, being born to a mother in poverty with limited access to prenatal and infant care substantially raises the risk of dying in the first year. Thus, cutting back on funding for health care services at the same time that infant poverty rates in this country were increasing raised the risks of infant mortality for these babies.

The Effects of Low Birthweight

Helping low birthweight newborns to survive is often only part of the medical care they will require. The Institute of Medicine (IOM) Committee to Study the Prevention of Low Birthweight, convened in 1982, found that many of these babies are at increased risk for a number of health problems, which in turn engender financial and family stresses. In its 1985 report, Preventing Low Birthweight, the committee notes "this increased risk has implications for health services, and possibly for educational services and family function as well."

Health Problems

Neurodevelopmental Handicaps

The most obvious side effect of low birthweight is the substantial prevalence in these youngsters, as they grow, of such neurodevelopmental handicaps as cerebral palsy, seizure disorders, and other neurologically based deficits. Low birthweight infants are three times as likely as normal-weight babies to have neurological problems, and the risk increases with every decrease in weight level.

Congenital Anomalies

Because defects can cause premature birth, immature infants are twice as likely as newborns of normal weight to have a serious inborn defect; in very immature babies these anomalies occur three times as often. They range from having extra fingers or toes, strabismus (a condition in which the muscles that control the eye are weak, affecting eye alignment and vision), to serious brain or heart defects.

Respiratory Tract Problems

The lungs of low birthweight babies often are immature, and the infants may have respiratory distress syndrome or hyaline membrane disease. As they grow up, such children may experience repeated lower respiratory tract infections and abnormal lung functioning. The persistence of these problems is particularly common among children who as newborns required prolonged ventilator support.

Side Effects of Technology

The technology used today to diagnose and treat low birthweight newborns can have deleterious effects on the baby. Best known is the effect of oxygen administration on the eyes of immature infants: It may cause retrolental fibroplasia, severely damaging eyesight and sometimes causing blindness.

The increased incidence of problems experienced by low birthweight babies means a greater use of health care services. In its report on these infants, the IOM committee said:

The length of hospital stay in the neonatal period for infants who survive to the first year of life averages 3.5 days for normal birthweight infants, but is much longer for smaller infants: 7 days for those between 2,001 and 2,500 grams at birth; 24 days for those between 1,501 grams and 2,000 grams; 57 days for those less than 1,500 grams; and 89 days for those less than 1,000 grams.

The committee found that in addition to the lengthy hospital stays many of these babies require when they are born, a substantial proportion of very immature newborns are rehospitalized during their first year and require more physician visits.

Family Stresses

Not surprisingly, the birth of an immature infant who requires intensive hospital care and may have chronic, sometimes disabling physical problems can produce tremendous stress on the family. The bonding between mother and baby often is disrupted, and a great deal of anxiety is produced by the infant's critical condition. These factors can also have a negative effect on later parenting behavior and on the interaction between the parents and the child.

Financial Stresses

The cost of the intensive medical care needed by immature infants frequently is enormous. Even families with insurance still must pay as much as 20 percent of hospital charges. Families without insurance often must pay as much as one-third of the total hospital bill. According to studies by the Alan Guttmacher Institute, the average bill for the delivery and care of a healthy baby is about $4,300, or one-fifth of the income of a typical young couple.

If the birth is complicated, the bill can easily be higher. The OTA found that in Maryland in 1986 the extra cost for hospital care for a low birthweight infant was $5,236. (That year the average hospital cost per admission in Maryland was within one-half percent of the national average.) A study at the University of Pennsylvania found that if an infant was discharged earlier and received follow-up nursing care at home, the cost of its hospitalization could be reduced by 25 percent, lowering the hospital charge for the infant's medical care to an average of $3,763. The average 1986 hospital charge for the care of a normal-weight newborn was $658.

Low birthweight babies have higher rates of respiratory, gastrointestinal, and infectious illnesses than do infants born at normal weights. Compared to normal-weight newborns, twice as many low birthweight babies are rehospitalized at least once during their first year. The extra cost of rehospitalization is conservatively estimated by the OTA at about $800 per low birthweight child. This does not take into account doctors' fees or the high rates of hospitalization of very sick premature infants who did not survive infancy.

A large proportion of low birthweight infants are born to families living in poverty and to teenage mothers who do not qualify for Medicaid under individual state criteria. In many of these cases the cost of care for a low birthweight child is carried by the hospital and passed on to the public. In addition, many working families have no health insurance or have insurance that provides only limited coverage. As a result, the cost of caring for low birthweight babies is borne by the public.

Preventing Low Birthweight: The Role of Prenatal Care

Studies demonstrate that infant mortality and low birthweight can be alleviated if the pregnant mother receives sustained, quality medical care beginning early in her pregnancy, so that incipient problems can be detected and corrected before they affect the fetus. Newborns whose mothers had no prenatal care are almost five times more likely to die than babies born to mothers who had early prenatal care. Good comprehensive care includes screening for potential problems; education and counseling about the connection between nutrition, life-style, and pregnancy outcome; and medical treatment as needed.

Almost all studies of prenatal care have some methodological shortcomings; despite this, a review of more than 55 studies by the OTA revealed that the weight of evidence "supports the contention that two key birth outcomes—low birthweight and neonatal mortality—can be improved with earlier and more comprehensive prenatal care, especially in high risk groups such as adolescents and poor women."

Cost-Effectiveness of Prenatal Care

Although the value of prenatal care is unquestioned, what is not yet clearly understood is exactly which preventive measures are effective and when during a normal pregnancy they should be applied. Also unresolved are questions regarding which components of prenatal care are most healthful and cost-effective and how best to reach the women who most need such care.

The OTA performed a cost-effectiveness analysis to determine how health care system costs would be affected if all pregnant poor women were enrolled in Medicaid, a policy made possible by the Omnibus Budget Reconciliation Act of 1987. "Poor" in this instance refers to women with incomes below 100 percent of the federal poverty level. The OTA estimates that offering such Medicaid eligibility would bring an additional 18.5 percent of poor women into prenatal care during their first trimester at a national cost of $4 million annually. The OTA also estimates that, for every immature birth prevented by better prenatal care, the U.S. health care system saves between $14,000 and $30,000 in expenses for newborn hospitalizations and long-term health services. For the savings to outweigh the costs, between 133 and 286 low birthweight births would have to be averted nationally among the newly eligible Medicaid users of early prenatal care.

Figure

To assure the best possible outcome for a mother and her baby, medical care plus nutritional, educational, and other support services are vital. Credit: National Institute of Child Health and Human Development

Current evidence suggests that it is indeed feasible to reduce the number of low birthweight births considerably well beyond the breakeven point. Several reasonably well-designed studies on the relationship between early prenatal care and birthweight have demonstrated effects that were at least twice as great as the effects needed for the Medicaid expansion to pay for itself. The OTA notes that early prenatal care also can prevent an unknown number of newborn deaths.

A study by Theodore Joyce and his colleagues at the National Bureau of Economic Research compared the cost-effectiveness of various health inputs and government programs in reducing race-specific neonatal mortality or death during the first four weeks of life. They found that early prenatal care was the most cost-effective strategy for reducing newborn mortality among both black and whites. Their analysis also revealed that blacks benefited more per dollar of resource use. Although neonatal intensive care was the most effective method of reducing infant mortality, it was one of the least cost-effective.

For the IOM study on the prevention of low birthweight, analysts calculated how fiscal outlays for the medical care for low birthweight infants might be reduced if expenditures for prenatal care for high-risk pregnant women were increased. They estimated that each $1 spent on prenatal care might save over $3 in medical care for such infants, if increasing the amount of prenatal care decreased the rate of low birthweight from the current 11.5 percent to the 9 percent level, the Surgeon General's 1990 goal for high-risk women.

The IOM committee observed that averting low birthweight births via comprehensive prenatal care will also reduce the risk of such disabling conditions as cerebral palsy and mental retardation, which frequently require long-term public assistance.

Who Isn't Getting Enough Prenatal Care?

Many women in the United States do not receive sufficient care: those who are still in their teens; who are black, Hispanic, or American Indian; who are unmarried; who are recent immigrants; who have less than a high school education; and who live in poverty. Each year at least 1.3 million women receive insufficient prenatal care, and many of them are the women who most need it.

Sufficient care is best defined as the amount needed to produce both a healthy baby and a healthy mother. The amount of care received in prenatal programs varies in the number of visits and therapeutic interventions. The American College of Obstetricians and Gynecologists (ACOG) and the American Academy of Pediatrics (AAP) have issued guidelines, but professionals disagree about the amount and content of prenatal care for normal pregnancies, about what constitutes a high-risk pregnancy, and about methods for handling high-risk pregnancies.

The ACOG and AAP guidelines call for maternity care visits to begin as early as possible during the first 3 months of pregnancy, continuing every 4 weeks until the 28th week, every 2 to 3 weeks until the 36th week, and then every week until delivery—a total of 13 to 15 visits. Such guidelines focus primarily on the number of visits rather than on their content. The OTA found that in the United States in 1984, 20 percent of white babies and 39 percent of black babies were born to mothers who had no prenatal visits during their first trimester. A substantial proportion did not even see a doctor until they were 7 months pregnant.

When the rate of adequate care rather than the trimester in which care was first obtained was reviewed, the prenatal care picture darkened. A 1985 study by Dana Hughes and others for the Children's Defense Fund found that only 68.2 percent of all women obtained adequate care, 23.9 percent received an intermediate level of care, and 7.9 percent had inadequate care. The definition of adequacy was based on a modified version of the Kessner Index, which cross-tabulates the timing of the first doctor's visit with the total number of visits made and the length of the pregnancy.

Teenagers

The percentage of babies born to mothers receiving late or no prenatal care varies significantly by age. Of all age groups, pregnant adolescents are the least likely to receive early prenatal care. This delay in receiving care is linked to the much-noted high risk of teenagers having low birthweight infants. In 1986 there were 472,081 births to women under the age of 20; 1 in 5 babies born to girls under age 15 and 1 in 8 born to mothers between ages 15 and 19 were low birthweight newborns. Almost 14 percent of all the low birthweight infants born in the United States in 1986 were born to adolescents under age 15, and 9.3 percent were born to adolescents aged 15 to 19.

Unmarried Women

Childbearing by unmarried women is on the increase in the United States. The greatest rate of this increase currently is among white women, although a black infant is still four times as likely as a white infant to be born to an unmarried woman. In 1986 the National Center for Health Statistics revealed that 23.4 percent of all births in this country were to unmarried women, a 6 percent increase over 1985. Unmarried women are much more likely to be poor, especially if they are adolescent mothers. As the Children's Defense Fund analysts note:

The proportion of births to unmarried women of all ages continues to increase, placing families at greater risk of poverty. In 1987 one in every two children living in female-headed households was poor. Among very young children living in households headed by single mothers younger than twenty-two, 88.8 percent were poor in 1987.

Blacks, Hispanics, and Native Americans

Black women are far less likely than white women to receive early prenatal care; they are twice as likely to receive no care or to obtain it late. Black infants are much more likely to die of causes that are usually considered preventable through comprehensive prenatal care.

Similarly, except for those of Cuban background, Hispanic women are much less likely than white women to begin prenatal care during the first trimester and three times as likely to receive either no care or late care. Cuban women, however, often are privately insured and are more accustomed than white women to begin prenatal care early.

In 1985 there were approximately 41,000 births to American Indian women and 112,000 to Asian or Pacific Islander women. Hawaiian women and other Asian subgroups, such as Cambodian, Vietnamese, and Korean, received late or no care at a rate somewhere between black and white women. Native American women were the most likely of all ethnic groups to receive insufficient care.

Immigrant women are also at greater risk of receiving little or no care during their pregnancies. Differences in local health care systems, language, and ethnic attitudes toward such care may keep them from obtaining prenatal services.

The Poorly Educated

The IOM Committee to Study Outreach for Prenatal Care, which began its work in 1986, found that education was an important factor in receiving prenatal care. The timing of the first prenatal visit correlated highly with education levels. In 1985, 88 percent of mothers who had some college education began care during their first trimester, while only 58 percent of women who had less than a high school education sought care early. The effect of education may be modified by ethnicity and other factors.

Women with Many Children

The more children a mother has, the less likely she is to obtain prenatal care. Fourteen percent of women pregnant with their fifth child received late or no care, compared with close to 5 percent of mothers having their first or second child.

Women Living in Poverty

Poverty is one of the most important factors consistently associated with insufficient prenatal care. A review of the data from the 1980 National Natality Survey shows that women whose incomes were at or below 150 percent of the federal poverty level were three times more likely to receive no prenatal care or late care than women whose incomes were equal to or above 250 percent of the poverty level. An analysis of data from the 1982 National Survey of Family Growth found that only one-half of women living below the federal poverty level obtained maternity care in their first trimester of pregnancy. The 1985 Massachusetts prenatal care survey revealed similar findings: Only 38 percent of women with yearly incomes of less than $10,000 obtained adequate prenatal care, while adequate care was received by 64 percent of women whose incomes fell between $10,000 and $20,000. When family income reached the $40,000 to $50,000 level, the percentage went up to 88 percent.

Growth in real family income has been slowing since 1973, and between 1979 and 1986 the median adjusted income for the bottom two-fifths of all families fell 2 percent. Families with children have made no gains in real income despite a 16 percent increase in the number of working mothers. Economic burdens are particularly heavy for those with a family head under age 25. Between 1970 and 1986 the real median income of those families dropped by 43 percent. Because the minimum wage in terms of real dollars has declined 33 percent since 1981, a person with two children who works full time at the minimum wage will earn $2,500 less than the poverty level.

The Uninsured

Between 1978 and 1985 the number of Americans without insurance multiplied from 28 million to more than 35 million. Nearly one-fourth are young adults aged 18 to 24, including millions of young women in their peak childbearing years. Three-fourths of Americans who were uninsured in 1984 were workers and their dependents. Public health specialist Lorraine V. Klerman emphasizes that employment is no guarantee of either general health benefits or pregnancy benefits. Studies find that many women are employed in companies that do not offer health insurance. Unemployed women may not be covered by the insurance of their spouses or fathers.

Companies that employ fewer than 15 or that self-fund their insurance plans may not offer maternity benefits. Retail and service organizations, such as fast-food restaurants, where many women find employment, often do not offer comprehensive health insurance. Part-time workers seldom receive any medical coverage. Furthermore, the rapidly increasing costs of health benefits are leading many employers to drop part or all of their health insurance plans. Young couples, who have the preponderance of babies, often begin their work careers in jobs that pay poorly and provide inadequate health insurance coverage. Furthermore, young wage earners seldom have enough savings to cover gaps in their insurance.

The Alan Guttmacher Institute found that in 1985 a total of 14.6 million women of childbearing age had no insurance coverage for maternity care. Of this number, 9.5 million women had no health insurance of any kind. Those most likely to be uninsured are teenagers and poor women who either are unemployed or are working at low-paying jobs. Their lack of insurance poses a serious problem, because they are most at risk for adverse (and expensive) pregnancy outcomes if they do not get early and comprehensive care.

Dr. Klerman also pointed out that women who do have maternity coverage may still not get adequate maternal care because of limits in benefits or because their coverage requires substantial cost sharing—strategies that are becoming increasingly common as the cost of health insurance rises. Medicaid covers only a small proportion of the poor.

A University of California, San Francisco, study found that in eight counties in California the number of newborns without health insurance rose by 45 percent between 1982 and 1986. The lack of health insurance was associated with an elevated and still-rising risk of adverse outcomes for the infants. The number of newborns requiring hospital stays longer than 6 days rose from 9,975 in 1984 to 14,411 in 1986. The researchers believe that the escalating risk of detrimental outcomes in uninsured newborns is ''explained most plausibly by diminished access to care, together with other factors related to lower socioeconomic status."

Obstacles to Prenatal Care

Inability to Pay

Studies suggest that one of the most important reasons women do not obtain adequate prenatal care is their inability to pay for it. As previously noted, many women do not have enough money to pay clinic or private physician fees, and many either have no insurance or their insurance policies do not cover maternity care. Although the 1978 Pregnancy Discrimination Act requires employer-based health insurance to include maternity benefits, the law applies only to the employee and spouse. As a result, 35 percent of typical family policies do not cover dependents such as teenage daughters for maternity care.

Only 25 percent of employer-based policies provide coverage for a teenager and her baby. This major gap in insurance coverage poses a serious problem because these young women are at especially high risk for adverse pregnancy outcomes and need early prenatal care.

Since its 1965 enactment, Medicaid has become the largest single source of health care financing for the poor, making medical services more accessible to more low-income individuals and families. Data from the National Center for Health Statistics reveal substantial increases between 1969 and 1980 in the number of women enrolling in Medicaid in order to receive early prenatal care. After 1981, however, the number remained static. After a survey of 51 Title V Maternal and Child Health agency officials in 1986, Sara Rosenbaum and her fellow researchers observed:

As private insurance coverage of the poor has ebbed, the growing deficiencies of the Medicaid program, the nation's largest public financing system for low income families, have grown more glaring.

The women who have enrolled in Medicaid have not obtained care as early or as often as women who have private insurance. There are numerous reasons: (1) In some states, Medicaid enrollment can be so time-consuming that many mothers are well into their pregnancies by the time they are eligible for care. (2) Medicaid enrollees often rely on clinics for care, and in some communities such clinics are so overcrowded that appointments must be scheduled for many weeks away. (3) Many private physicians who provide maternity care are unwilling to accept Medicaid or nonpaying patients, and others have reduced the number of such cases they will see. (4) Pregnant women on Medicaid often are, by definition, at the bottom rung of the economic ladder and are characterized by many other demographic factors associated with not seeking prenatal care, such as being under age 20, unmarried, and in fair or poor health.

In an effort to provide health insurance for more poor pregnant women, Congress passed new laws between 1984 and 1988 that made it possible for states to expand their Medicaid eligibility standards. The effect of one of the laws was to sever the connection between Medicaid and AFDC. The 1986 Omnibus Budget Reconciliation Act (OBRA) allowed states for the first time to offer Medicaid to pregnant women who had incomes up to 100 percent of the federal poverty level regardless of whether they were eligible for AFDC under the rules of an individual state. Forty-five states adopted this expansion. The 1988 Medicare Catastrophic Coverage Act required that all states extend their Medicaid coverage to this level by mid-1990.

Furthermore, the 1987 OBRA gives states the option of providing maternity care benefits to all pregnant women and infants whose family incomes are at or below 185 percent of the federal poverty level. The Children's Defense Fund in 1989 estimated that if all states exercise this option Medicaid eventually will be available to cover health care costs for nearly one of every two births in the United States.

Because some restrictive eligibility standards remain, however, a large proportion of near-poor pregnant women and infants still are ineligible for Medicaid assistance.

A Shortage of Clinics

It has been well documented that in some areas public health clinics, community health centers, and outpatient departments that could provide maternity care are in short supply. At the same time, the number of women who are uninsured and unable to pay for their maternity care is growing because the proportion of women who work part time or in low-paying jobs with limited or no health benefits also is growing. For these women publicly financed clinics are the only available resource. The shortage of clinics has led to long waiting times before a pregnant woman can be seen by clinic staff for an initial prenatal visit. Waiting periods are so long at some clinics that it is not possible to see every pregnant patient during her first trimester. Expanding clinic hours may not be possible if funds are not available to pay for additional staff time.

The IOM prenatal care study committee found numerous examples of overcapacity and a shortage of services:

In 1985 a survey of its 42 public health clinics by the Los Angeles County Department of Public Health found that waits for initial prenatal visits ranged from 2 to 14 weeks.

In Charleston, West Virginia, from 1982 to 1986 at least one clinic closed admissions periodically every year, sometimes for as long as 2 months, because its limited staff could not keep up with the high volume of patients.

During a 3-month period in 1986, public clinics in San Diego County were forced to turn away 1,245 women seeking prenatal care because the clinics were filled to capacity. Orange County, California, clinics could not give appointments to 2,000 women in 1985. Officials in these counties estimated that at least half the women who could not be cared for at the county health centers were unable to find care anywhere else.

A 1982 survey of private nonprofit New York City hospitals found waiting times that ranged up to 4 months for a first prenatal appointment.

Although community health clinics offering maternity health services have never been in oversupply, in recent years federal budget cuts coupled with a recession have forced local health departments to reduce their staffs at a time when the need for their services increased markedly. Some reported reducing or eliminating maternity or nutrition services, or both.

Physician Inaccessibility

The need for publicly supported prenatal care services has been exacerbated by a decrease in the availability of obstetricians and family practitioners who provide maternity care. Although the United States has no shortage of physicians overall, some areas do not have enough doctors and others have none at all. For example, Mississippi reported in 1983 that 51 of its 82 counties had no resident obstetrician. Eleven of 58 counties in California did not have an obstetrician and 9 of those counties had no public prenatal care clinic. Although the number of practicing obstetricians has been increasing, many areas still have few or none.

The presence of an adequate number of practitioners, however, does not make maternity care more accessible to poor and uninsured pregnant women, unless the physicians are willing to accept Medicaid or to reduce their fees for women who have no maternity coverage at all. Among primary care physicians, obstetricians have been the least likely to accept Medicaid patients, according to an early 1980s study of physician access.

In a 1984 survey of primary care physicians, 36 percent of obstetricians said they did not provide care to Medicaid patients. By comparison, 25 percent of general practitioners, 23 percent of pediatricians, and 20 percent of internal medicine practitioners did not accept Medicaid patients.

Physicians give many reasons for refusing to accept Medicaid patients: extensive paperwork, slow claims processing, long-delayed and uncertain payments, and reimbursement rates that represent only a fraction of the physician's actual costs or usual fee. This latter claim is borne out in a comparison of Medicaid versus the usual obstetric fees, which include prenatal care. Usual charges in 1986 averaged $830 for a vaginal delivery; the average Medicaid reimbursement was $554. Medicaid reimbursement rates have risen in recent years, yet they remain substantially lower than customary physician charges. In addition, the IOM prenatal care study committee reported:

The problem of low Medicaid reimbursement is exacerbated by the high proportion of Medicaid women who are high-risk patients. Because of multiple health and social problems, these women often need more frequent and comprehensive maternity care than more affluent women, and such extra care can be time-consuming and expensive to provide.

Indeed, the case could be made, the committee says, that because many pregnant women enrolled in Medicaid are at high risk, reimbursement for their care should be greater than the average obstetrical fee.

Restrictions on Nurse-Midwives

In both rural and urban areas, certified nurse-midwives and nurse practitioners have been especially effective and experienced in managing the care of high-risk pregnant women. Obstetric customs and, in many states, legal restrictions have limited the number and the scope of practice of nurse practitioners and nurse-midwives. Although in many European countries they provide the majority of maternity services, in the United States only some 2,600 nurse-midwives are actively practicing.

The Cost of Malpractice Insurance

Malpractice insurance premiums for practitioners who provide obstetrical services doubled between 1982 and 1985. The reasons are many and include changes in medical technology, changing standards of practice, and an increase in large awards and in the size of lawyer contingency fees.

Premium costs and increasing anxiety about the risk of a malpractice suit have driven many providers to discontinue their obstetrical services or to cut back the number of their obstetric patients. When the ACOG surveyed its members in 1983 and 1987, it found that, because of malpractice concerns, the proportion who reduced the number of high-risk patients they saw had increased from 18 percent to 27 percent. These physicians also had decreased the number of deliveries they performed, and a substantial number said they had stopped practicing obstetrics entirely.

A similar member survey by the American Academy of Family Physicians in 1986 revealed that 23 percent had stopped providing obstetric services because of malpractice concerns.

The malpractice situation has a particularly negative effect on public clinics, which are having a difficult time obtaining liability insurance and finding physicians willing to practice obstetrics. Chronically underfunded inner-city health centers often are forced to eliminate obstetric services because they cannot afford the insurance. As Sara Rosenbaum and Dana Hughes of the Children's Defense Fund point out:

Even though both Community Health Centers and nurse midwives have very low malpractice claims profiles compared to other providers of obstetrical care, their rates have risen dramatically. . . . At one center in Florida, malpractice coverage for prenatal care services is $4,000 annually per staff member. Coverage for delivery, however, would add $25,000 in costs per staff person.

Dr. Klerman advises that physicians may use the fear of malpractice suits as a reason for reducing or eliminating their Medicaid or uninsured caseload, due to an unsubstantiated belief that these women are more likely to sue. The recently published IOM study of medical professional liability and the delivery of obstetrical care found that this perception by physicians is not supported by the data available.

The committee notes that people with low incomes generally have less access to the legal system. In addition, medical malpractice actions are brought by attorneys on a contingency fee basis. Because awards usually are based on lost earnings, among other things, it would appear that attorneys have less financial incentive to serve poor plaintiffs. A Government Accounting Office study of malpractice claims found that the average expected payout for a Medicaid plaintiff was $52,000; the average for a privately insured plaintiff was $250,000.

Most studies regarding the relation of income to medical malpractice suits do not bear out doctors' perceptions that they are at greater risk of being sued by poor or Medicaid patients.

The Programs

Lack of Coordination Among Programs

Five principal federal programs supply prenatal care and related services to low-income women: Medicaid; Maternal and Child Health Services Block grants; the Special Supplemental Food Program for Women, Infants, and Children; community health centers; and migrant and rural health centers. Each has a different function and, if they could work together, they would furnish pregnant women with many of the maternity services they need.

Unfortunately, the programs often are not well coordinated at the community level; their connections to other public services and to private physicians range from weak to nonexistent. The IOM prenatal study committee found that coordination between programs can be difficult because each is independently organized and has its own administration, rules, and constraints. A woman may be eligible for Medicaid coverage and for prenatal care services from a local health department clinic, but enrolling in both may require meeting different eligibility standards, applying at different sites, completing different applications, and furnishing different documentation.

Pregnancy testing services are another example of poor coordination among programs. Although testing services may provide the telephone numbers of prenatal clinics, many services do not have close ties to prenatal care clinics. The lack of a direct relationship does not help women whose pregnancy tests are positive to make an appointment for the important first-trimester evaluation. Close ties to prenatal care clinics would expedite appointments, making it easier for clients to start maternity care.

Medicaid Application Procedures

Medicaid is the major source of payment for prenatal services obtained by pregnant poor women, yet rates of enrollment among women eligible for the program vary as much as 11 to 84 percent from state to state, and many eligible women do not enroll. The masons are many. Medicaid programs rarely publicize their benefits or explain how to enroll, and their brochures seldom note that pregnancy may be grounds for eligibility. Although a few states have streamlined their enrollment procedures, in many they often are excessively complicated. Application forms can run from 4 to 40 pages, and a typical form may include 80 to 100 questions. Completing an application often requires two or three trips to the Medicaid office and long waiting times, and eligibility can be denied on the basis of a single missing document, such as a utility bill. In addition, eligibility must be redetermined periodically during pregnancy; changes in household composition or expenditures can stop Medicaid coverage in the middle of a pregnancy, unless the state has adopted the continuous eligibility option. The long waiting periods between making an application and receiving a Medicaid card make it difficult to receive prenatal care during the first trimester. Even physicians and clinics who accept Medicaid as payment may insist that the enrollment process be completed and the patient have her card in hand before they schedule an appointment.

As the IOM committee observed,

The difficult application process, the complexity of the program and the great variations in the program across states create the impression of a system designed to discourage rather than encourage entry into prenatal care.

Although the committee noted that Congress and the states have taken steps recently to broaden Medicaid eligibility, it also observed that the program remains limited in its ability to draw low-income women into prenatal care promptly and with a minimum of bureaucratic harassment.

Other Barriers

The traditional obstacles to receiving early and regular care continue to hinder women from receiving necessary services. Long-standing barriers include the following.

Transportation

These impediments to care include the need to travel long distances to reach a clinic, the high cost of transportation, and no means of transportation at all. In some cities poor neighborhoods have limited public transportation services, and rural areas often have no bus or rail services. The IOM committee pointed out that the lack of a car and the transportation problems that result have become a mark of poverty and can form insurmountable barriers to obtaining health services.

Child Care

If a woman already has children, her use of prenatal health services is affected by the availability of child care. If she can not find or afford a babysitter, she may have to bring her children with her. If there are long waits at the clinic and child care is not provided, the burden of taking the children may outweigh any perceived benefits of the visit.

Clinic Hours

The problems of accessibility created by the need to travel long distances, inadequate transportation, and lack of child care are exacerbated by limited clinic hours. Most clinics are open only on weekdays from 8 or 9 a.m. to 5 p.m., making it difficult for women who work or go to school to schedule appointments. Women in low-paying jobs lose wages for time not worked or risk disapproval for taking time off. When some District of Columbia clinics began offering prenatal appointments during the evening and weekends, the number of patients seeking care at those clinics increased markedly.

Long Waiting Times

Long waits are common in publicly financed health centers, particularly in those using the block appointment system. In that system women are told to come either at 8 or 9 a.m. or at 1 p.m., and then they are seen on a first-come, first-served basis. For most patients this means a wait of 2 to 3 hours, an experience patients describe as frustrating and humiliating. It can also be costly in terms of time lost from work or in child care expenses. A study of low-income prenatal care patients in New York City found that the women viewed long waiting times as a sign of the staff's disregard for the value of their time; they said it was especially insulting to wait several hours and then have only a few minutes with a physician.

Staff Attitudes

The use of prenatal care can also be influenced by the way clinic staff treat patients. Seeing a different doctor each time, receiving hurried or impersonal care, and dealing with rude or indifferent appointment clerks or receptionists discourage patients from continuing prenatal care. Socioeconomic differences between staff and patients may add to an already negative atmosphere, and language differences compound the problem. Even something as simple as not having enough chairs for waiting patients conveys the message that the patients are not wanted.

Hiding the Clinic

Few clinics let prospective patients know the clinic location or how they can make appointments. Studies report that 5 to 18 percent of women who received little or no prenatal care before the birth of their child did not know where to find such services. The IOM committee found that few telephone directories have a listing for "prenatal care" or a similar phrase.

Cultural and Personal Barriers

Personal attitudes and the cultural characteristics of the pregnant woman can also impede adequate prenatal care. The IOM panel found that the use of prenatal care is affected by the woman's attitude toward her pregnancy and prenatal care, whether she views such care as useful, and by her cultural values and beliefs, her life-style, and certain psychological characteristics.

Attitudes

Whether a woman makes an effort to find prenatal care appears to depend on how she regards her pregnancy. If it is unplanned and she views it negatively, she is more likely to delay care and to make infrequent clinic or physician visits. Accordingly, most observers feel that a reduction in unplanned pregnancies would lessen the incidence of late care.

Not all women feel that prenatal care is important. Some believe that pregnancy is a normal function and that medical care is needed only when a pregnant women is unwell.

Failure to recognize the signs of pregnancy also is a factor in delaying care. Studies demonstrate that between 16 and 33 percent of the women who did not receive sufficient care did not know for some time that they were pregnant. This is particularly true of first-time pregnant women, especially those still in their teens. "Not knowing I'm pregnant" also is a form of denial, a marker of an unintended and usually unwanted pregnancy.

Fears can be substantial barriers. They can include fear of medical personnel or procedures, fear of the reaction of others to the pregnancy, fear that one's status as an illegal alien may be discovered, and fear of pressures to change life-style habits such as substance abuse, smoking, or eating disorders. For some women the stress and pressures of their lives may prevent them from obtaining adequate prenatal care. Anxiety about lack of money, housing difficulties, difficulties with the baby's father, lack of emotional support, and other problems can interfere with finding care.

Denial also interferes with the use of prenatal care. Although this can be seen in women of any age, it is most prevalent among teenagers. As noted in Chapter 4, some adolescents simply do not want to believe that they can get pregnant. The denial continues into pregnancy. Frank F. Furstenberg's survey of teenage mothers in Baltimore found that half the adolescents did not tell their mothers about their pregnancy until several months had elapsed.

These psychological problems are difficult to correct, particularly through public policy procedures, Dr. Klerman observes. But she believes that increased funding for Medicaid and for public prenatal clinics, changes in private insurance regulations so more women are covered for maternity care, and aggressive outreach and educational campaigns will help appreciably and are within the scope of national and state legislative concerns. She adds that, ''Attention should be paid to these items, rather than blaming the victim for neglect of needed care."

Homelessness

Not surprisingly, women who are homeless and living in shelters have difficulty obtaining prenatal care. Forty percent of pregnant women living in hotels for the homeless in New York City during 1982 and 1984 received no care at all.

Substance Abuse

Pregnant women who are aware that their life-styles risk their health and the health of their babies may also be afraid to seek care because they expect pressure to change such habits as heavy smoking, eating disorders, or the abuse of drugs or alcohol. Substance abusers, especially, may avoid seeking prenatal care because of the disorganization and stress in their lives. They also fear that their drug use will be discovered, they might be arrested, and their other children might be taken into custody.

Several recent studies show that a significant number of women in the childbearing years of 18 to 35 frequently use cocaine and other drugs. Substantial percentages of women who obtain prenatal care late or not at all abuse drugs, particularly heroin and cocaine. The number of babies who test positive for a variety of illegal drugs is increasing steadily in the United States, particularly in large cities. The babies of drug-using mothers often have multiple problems that may require intensive care and long hospital stays: low or very low birthweight, drug addiction, neurodevelopmental disorders, and congenital defects.

A study of 75 cocaine-using mothers and their infants by Dr. Ira Chasnoff, of Northwestern University Medical School, found that many women who use cocaine become pregnant without realizing it and continue to use the drug. Even if they give up cocaine after the first trimester, these women remain at high risk for miscarriage. If they continue to use cocaine throughout their pregnancy, they increase their risk of having a preterm delivery and a low birthweight infant or of having a full-term baby who is smaller than normal.

A study of 1,226 infants and mothers at Boston City Hospital by Barry Zuckerman and other researchers from Boston University had similar findings. All the women were drawn from the prenatal clinics held by the hospital. Approximately half the women used marijuana or cocaine; in all other demographic characteristics, including use of cigarettes and alcohol, the women's backgrounds were similar. Drug use was determined by urinalysis, self-reporting, or both. The majority of mothers in this study were low-income women and most were single.

In all measures of newborn growth, the infants whose mothers used marijuana or cocaine were significantly smaller than the babies born to nonusers. In addition, babies born to cocaine-abusing mothers were at greater risk of being premature. With one exception, congenital malformations were not significantly more frequent among babies born to mothers who used these two drugs. Among the babies of cocaine users, however, the proportion of one major or three minor congenital problems was considerably larger (14 percent versus 8 percent) than among the infants of nonusers.

Dr. Zuckerman and his colleagues point out that many of the women who used drugs also exhibited a life-style associated with depressed fetal growth. They used alcohol and cigarettes, and the pregnant cocaine users also were found to have a greater incidence of sexually transmitted diseases. Cocaine users weighed less before pregnancy and gained less during its course. In the presence of these multiple risk factors, the researchers note, the use of cocaine or marijuana further impairs fetal growth. Although pregnancy may serve as an impetus for a woman to stop using alcohol or cigarettes, drug users appear to find it much more difficult to abstain during pregnancy.

Research Needs

Although many agencies and programs help provide health care to pregnant women and young children, increasing numbers of pregnant women do not receive maternity care until the third trimester or obtain no care at all. Health care professionals have suggested several approaches for drawing into care those low-income women who are at elevated risk for poor pregnancy outcomes. Some advocate scrapping current national programs and instituting a new comprehensive one; others recommend changing current services so they can reach more women and provide care in a coordinated, user-friendly way. More research is needed on these issues:

A basic understanding of the mechanisms that underlie inadequate intrauterine growth and the premature onset of labor is necessary to develop preventive measures.

The programs that are most successful in bringing women into prenatal care early and in keeping them there should be identified.

When financial and access barriers are reduced, what can be done to bring into care those women who have psychological problems or educational deficits that prevent them from seeking prenatal care?

Do regular home visits by health care personnel help increase a pregnant woman's compliance with medical recommendations? What is the minimum number of visits that are useful?

What programs are successful in helping pregnant women change the life-styles that endanger the health of the fetus?

What services can be offered to drug-addicted women and how and where should such services be made available in order to keep these women in care both for their pregnancy and to treat their addiction?

Teenagers and other young unmarried women need to be made more aware of the importance of prenatal care; identifying the most influential and cost-effective components of educational programs would be useful before large-scale efforts are designed.

Conclusion

Since the beginning of this century, the infant mortality rate in the United States has steadily declined. That decline slowed during the 1980s, showing almost no progress from 1984 to 1986. Several factors are implicated in this leveling off of infant deaths: a deepening of poverty in the United States; a more careful reporting of extremely low birthweight infants who die almost immediately, which in the past would have been reported as fetal deaths or would have gone unreported altogether; a continuation of the large proportion of births to teenagers and unmarried women, who often have low birthweight babies; and an increase in the percentage of women receiving prenatal care late or not at all.

The effect of these factors has been exacerbated by an increase in the number of women, particularly young women, who are not covered by maternity insurance, by the difficulty and the delays that pregnant women experience when they try to enroll in Medicaid, by a decline in the number of physicians accepting low-paying Medicaid patients, and by a lack of coordination among clinics. In general, the picture is one of more women being at risk for having babies who are preterm or whose fetal growth has been retarded, while at the same time services to improve the health of such mothers and their infants are reduced and fragmented.

Acknowledgment

Chapter 5 was based in part on a presentation by Lorraine V. Klerman.

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